In the 3rd Generation Partnership Project (3GPP) Long Term Evolution-Advanced (LTE-A) working groups, heterogeneous networks having a macro evolved Node B (eNB) along with one or more remote radio heads (RRH) or remote radio units (RRU) are being considered. Heterogeneous networks utilizing a diverse set of eNBs with different transmit powers can be deployed to improve coverage and spectral efficiency in cellular communication systems.
In one embodiment, a heterogeneous network with macro eNB and multiple RRHs can use a shared cell identifier (ID) to support both legacy user equipments (UEs) and advanced UEs with coordinated multi point (CoMP) capability. Specifically, in 3GPP LTE-A, CoMP transmission schemes have been proposed to improve spectral efficiency though coordination among multiple transmission points.
However, the design of a heterogeneous network with shared cell identifiers needs to redesign various Long Term Evolution capabilities, including the random access channel (RACH) process, transmission point association, and uplink power control.